1. Field of the Invention
The present invention is generally related to flush valves for water closets, urinals, and the like and, more specifically, to an electric power generation device for use with such a flush valve.
2. Description of Related Art
Hydroelectric power generation in which kinetic energy is extracted from flowing pressurized water and used to rotate a generator to produce electric power is known. With large hydroelectric power generation operated with a large-scale water source such as a river or dam, thousands of megawatts of power may be generated using millions of gallons of flowing water. As such, conversion of the kinetic energy in the flowing water to electric power may include significant inefficiencies and yet still provide an economical and acceptable level of performance.
Automatic plumbing fixtures, such as toilet valves and sink faucets, may include an electrically operated valve and a sensor. The sensor may sense the presence of a user of the automatic plumbing fixture and operate the electrically operated valve to provide a flow of water in response. Both the electrically operated valve and the sensor require electric power to operate. The power may be obtained by installing an electric cable from a power distribution panel to the automatic plumbing fixture. Where the automatic plumbing fixture is installed in an existing building, installation of a power distribution panel and/or an electric cable can be costly, time consuming, and difficult. Accordingly, hydroelectric generators for use with such plumbing fixtures have been developed. However, it is difficult to generate enough power using such a small hydrogenerating device and small-scale water source.
For instance, U.S. Pat. No. 7,253,536 to Fujimoto et al. is directed to a toilet bowl flushing apparatus (1) including an apparatus body (6) disposed in the inside of a casing (5). The apparatus body (6) includes a cylindrical water inlet (10) which is communicably connected with a water supply pipe (2) and a cylindrical water outlet (11) which is communicably connected with the toilet bowl (3). The apparatus body (6) further includes an open/close valve (12) disposed on a downstream side of the water inlet (10), and an electromagnetic valve (18) connected with a control unit (20). A power generating unit (23) including a holder (26), an impeller (27), an intermediate cover (28), a coil (29), and a cover (30) is also positioned within apparatus body (6). However, the power generating unit is positioned within apparatus body (6) such that only a portion of the water received from water supply pipe (2) passes over the impeller (27). Accordingly, a large amount of the energy of the water from water supply pipe (2) is lost and not converted into electrical energy.
In addition, U.S. Pat. No. 7,233,078 to Baarman et al. discloses a urinal (2100) that is included as part of the hydro-power generation system. The urinal (2100) includes a water inlet (2102) for receiving water and a water outlet (2104) for discharging water. The urinal (2100) also includes a valve module (2106), an electronics module (2108), and a power generation module (2110). The valve module (2106) includes an electrically operated valve (2202). Upon energization, the electrically operated valve (2202) may move to a position that opens a liquid flow path through the valve module (2106). When the liquid flow path is opened, pressurized liquid supplied at the inlet (2102) may flow through the valve module (2106) and the power generation module (2110) to the outlet (2104). Upon de-energization, the electrically operated valve (2202) may close off the liquid flow path, stopping the flow of liquid through the valve module (2106) and the power generation module (2110). The power generation module (2110) includes an outer housing (1102), an inner housing (1104), a centering rod (1106), and a nozzle (1108). The outer housing (1102) also includes a scupper (2204) to channel liquid toward the outlet (2104) following impact with the inner housing (1104). The inner housing (1104) pressurizes liquid provided to the inlet (2102) which is accelerated to a high velocity by the nozzle (1108) and directed in a stream of liquid at the paddles (1118) positioned on the outer surface of the inner housing (1104). Like with the Fujimoto patent, only a small portion of the water received from the water inlet (2102) is directed through nozzle (1108) onto the paddles (1118) of the power generation module (2110). Therefore, a large amount of the energy of the flowing water is lost and not converted into electrical energy.
Accordingly, a need exists for an efficient hydrogenerator device for use with a plumbing fixture. More specifically, a need exists for a hydrogenerator device that directs substantially all of the water from a water inlet over the blades of a rotor to efficiently generate electrical power from the flow of water.